Ronja obviously has two independant sources:- According to the Astrid Lindgren biography by Sybil Gräfin Schönfeldt, Lindgren took the name from a map of northern Sweden, there it is a mountain called AnRONJAkåtan. - In Russia Ronja is a pet form either of Weronika or of Roxana.It looks like Mrs. Lindgren was not aware of this.